David Bowie was considered for Gandalf's role: Amy Hubbard

After a long speculation about whether the music icon David Bowie was ever considered for Gandalf's role in "The Lord of the Rings" series, the casting director Amy Hubbard has confirmed the news, saying they indeed approached him for the part.
Earlier this year, original "Lord of the Rings" cast member, Dominic Monaghan revealed that he once had an encounter with Bowie when he went to the casting agency to audition for his role of Meriadoc Brandybuck and the actor assumed that the late iconic rocker was there for the audition of bearded wizard.
Speaking to The Huffington Post, Hubbard finally addressed the speculation, saying Bowie was indeed considered to play Gandalf. However, Hubbard said the singer never auditioned for the role that ultimately went to Ian McKellan.

"He was unavailable. It was a very quick conversation with the legendary Chris Andrews at CAA. I do believe that (Bowie) went over and played for everybody at the Millennium party. That would've been New Year's Eve in the year 1999, which was when the films were being shot.
"He went over and entertained everybody, but he never auditioned. That's for sure."
She further said that Peter Jackson, the director of "The Lord of the Rings" trilogy, wanted Bowie to play the popular fictional character.
"We approached him. I'm pretty sure it was Peter Jackson's idea in the first few weeks that we got going. It was one that he'd always wondered about, and we rang Chris, and (Bowie) was far too busy," Hubbard said.